<?php
    //使用方法：将本文件拷贝到系统根目录下执行即可
    set_time_limit(0);
    if (isset($_GET['dir'])){ //设置文件目录

    $basedir=$_GET['dir'];

    }else{

    $basedir = '.';

    }

    $auto = 1;

    checkdir($basedir);

    function checkdir($basedir){
    	if ($dh = opendir($basedir)) {
    	  while (($file = readdir($dh)) !== false) {
    	   if ($file != '.' && $file != '..'){
    		if (!is_dir($basedir."/".$file)) {
    		 echo "filename: $basedir/$file ".checkBOM("$basedir/$file")." <br>";
    		}else{
    		 $dirname = $basedir."/".$file;
    		 checkdir($dirname);
    		}
    	   }
    	  }
    	  closedir($dh);
    	}
    }

    function checkBOM ($filename) {

    global $auto;

    $contents = file_get_contents($filename);

    $charset[1] = substr($contents, 0, 1);
    $charset[2] = substr($contents, 1, 1);
    $charset[3] = substr($contents, 2, 1);
    if (ord($charset[1]) == 239 && ord($charset[2]) == 187 && ord($charset[3]) == 191) {

      if ($auto == 1) {

       $rest = substr($contents, 3);

       rewrite ($filename, $rest);

       return ("<font color=red>BOM found, automatically removed.</font>");

      } else {

       return ("<font color=red>BOM found.</font>");

      }

    }

    else return ("BOM Not Found.");

    }

    function rewrite($filename, $data) {
    	$filenum = fopen($filename, "w");
    	flock($filenum, LOCK_EX);
    	fwrite($filenum, $data);
    	fclose($filenum);
    }